Plaster surfaced building board



May 3, .1932. c. A. uPsoN PLASTER SURFACED BUILDING BOARD Filed July 17, 1929 INVENTOR K @rales/U 502i/ ATTORNEYS Patented May 3, 1932 UhliTED STATES atrasos PATENT @FFQE CHARLES A. UESON, OF LOCKPORT, NEW YORK, ASSIGNOR TO THE UPSON COMPANY, OF LOQKIORT, NEW'YORK, A. CORPORATION OF NEW YORK BLASTER SURFACED BUILDING BOARD Application filed July 17, 1929. Serial No. 379,053.

My present invention'relates to building material, and more particularly to plaster wallboard whether the plaster is applied after the`rest of the wall is in place, or whether it is desired to first apply the plaster as an outer nishing surface to a ready-toapply wallboard, and the invention has for its object to provide an improved structure of this character which can be rapidly and cheaply produced; 'which will have higher wearing and insulating qualities, and in which, particularly, the plaster surface will be intimately and effectively locked to the supporting body. The improvements are further directed toward so reinforcing the wallboard that, as a ready-to-apply article, it will not stand in danger of breakage either in yshipment or in handling during the operation of applying it to the wall.

To these and other ends the invention resides in certain improvements and combinations of parts', all as will be hereinafter more Vfully described, the novel features being pointed out in the claims at the end of this specification.

ln the drawings:

Fig. l is a perspective view of a fragment of a wallboard before'it has received its plaster surface, the same being constructed in accordance with'and illustrating one embodiment of my invention, the .several elements composing the same being shown cut away from each other in different parallel planes to better illustrate'v the composite makeup.

Fig. 2 is a section through the board shown in Fig. 1;

Fig. 3 is a similar sect-ion with the plasterv surface applied;

Fig. 4 is a section through a fragment of a modified form of the board before plasterv dated May 10, 192i entitled Molded product and process for its manufacture, and Kem-- per Slidell, No. 1,655,714, dated January 10, 1928, and entitled Machine and method for making wallboard, to which reference is suggested. lt will be understood, however, as indicated by the claims, that my invention is not limited to the operation, materials, and

heated platens, whereby the material is pued into a highly cellular or porous sheet with smooth Hat paper surfaces. When the sheet is hardened by further heat treatments and drying it is transformed into a rigid coherent mass having great insulating qualities and the cells of which are larger or smaller ac-l cording to the proportion of the component elements employed.

Y This application is a continuation in part of my prior pending application, Serial No. 333,150, lield January 17, 1929, and in the practice of this invention as well as that disclosed and claimed in my said copending application, l prefer to use these inventions just outlined, arranging to produce a relatively large ce lli1lar structure in the intumescentinorganic material, but in one embodiment of my present invention, l use only one ofthe outside paper liners described in Patent No. 1,655,714, aforesaid, and referring to Figs. 1 and.2vin which this embodiment is illustrated 1 indicates the heavy paper liner,

and 2 the intumescent body which has been caused to adhere thereto firmly by the pufng process. It will be seen from an inspection of Fig. 1 that the' outer face of the body 2 opposite to that which is attachedto the paper liner or backingl has a roughened irregular pitted surface represented by the pores or cells which are only partly formed in the body of the material and open on .that surface. In the further practice of my invention I apply to the surface a layer 3 of ordinary plaster in the plastic state by smearing it over and working it into the same, giving the eX- terior the usual smooth or any preferred decorative surface.. The soft plaster permeates the open surface cells of the body 2 and becomes locked therein due to their irregular conformation, as clearly shown in Fig. 3.

This is preferably done in the production of the wallboard before it is applied to the wall, it being cut to size and allowed to harden, after which it is more compact and lcan be handled with greater safety than any latter is placed in final position on the wall.

To further strengthen the board of the present invention without appreciably increasing its thickness, I prefer to place centrally of the cellular body 2 of intumescent material a sheet or layer 5 parallel to the liner 1 and composed of the same heavy paper or other suitable material. This may be run in Iwhile the dough-like mix of the said Slidell patent is in its plastic condition between the forming rolls. This tough intermediate lamination is firmly imbedded in the cellular mass when cooled and hardened adhering thereto with the same tenacity as does the liner 1. The tensile strength of the body 1 is less than its resistance to compression and when abending force is exerted on the wallboard in either direction, one of these elements 1 and 5 takes the tension stress, which it1 is well adapted to bear. Without this intermediate reinforcement, the board as iirst describedl would have a greater tendency to break when bent so that the tension stress would come upon the body 2 and the plaster 3.

Figs. 4 and 5, as before stated, illustrate anot-her method of applying the plaster surface to the article which is somewhat better adapted to the process of the patents referred to if this is to be utilized in making upv the cellular body element. In drawingthe back ing liner 1 and the body 2 through the heated `platen diliiculties may arise owing to a tendseney on the part of the intumescent plastic 2 to stick to the heated platens. To avoid this I may use, in addition to the heavy liner 1 a very light tissue-like liner 4 on the opposite or buter face, the same being composed of the verythinnest paper that can be fedto the ma- 'chine- When, however, the plaster body 3 is applied as before to furnish the desired surface, this tissue 4 becomes saturated by the wet plaster and is destroyed as a liner, permitting the plaster in its plastic state to perifneate the cells and lock into the same as beore.

It will be understood that my reference to the two existing United States patents aforesaid is merely an illustration of one manner of accomplishing the desired results of the present invention in the production of a suitable cellular body on a. backing to take the plaster surface, and it is to be understood further that, in the broad aspectsv of my present invention, this body element may be produced in other ways.

In using the general process of manufacture first above recommended wherein the intumescent material containing silicate of soda as a principal ingredient is passed between the heated platens, I have found that sometimes the hot silicate attacks the tissue paper liner 4 in a manner rendering it hard and brittle, whereas the best interests of this invention are served by maintaining the tissue paper soft and water absorbent. Under lthe heat treatment, the tissue paper seems to swell and then bake and become rather tough vso that it does not wholly break down over the little cells of the porous filler in appl ing the wet plaster. This tendency may ge counteracted by using an oiled or waxed paper or otherwise impregnating it so that it will resist the entrance thereinto of the silicate ingredient that is responsible for the deleterious result.

The word plaster as used in the specification and claims is intended in'a broad generic sense and includes any plastic material suitable for use as a finishing or coating over the porous or cellular body. Although liners or backing members of paper have been speciically mentioned as examples, it is obvious that the liners or backing or reinforcing members may be of any suitable material and may be treated in any suitable way.

I claim as my invention:

1. A plaster wall support embodying a backing liner, a hardened, intumescent cellular body adhering thereto on one side', and a thin tissue liner covering the surface of the cellular body on thevother side and adapted to be disrupted and destroyed as a liner by the application of wet plaster van permit the latter to permate the open cells of the intu- "mescent body beneath it. i Y 2. Amaterialfor constructionpurposescomprising an intumesced cellular body having an exposed cellular face adapted to receive facing material, a liner of reinforcing material adhering to said `cellular body on one side thereof, and a layer of reinforcing material imbedded in said cellular bodyintermediate the sides thereof.

CHARLES Y A. U'PsoN. 

